Meet The New LT1 V8 For The C7

Earlier this morning, General Motors debuted a brand new 6.2L LT1 V8 engine that will be in the seventh-generation Corvette.The new LT1 is full of new tech and comes with some impressive specs.

The new 6.2L V8 will produce 450 HP and 450 pound-feet of torque. That can propel the C7 to 60 in under 4.0 seconds, which puts it within a hair of the 2012 Corvette Z06's 0-60 time of 3.7 seconds. Fuel economy is impressive, with GM claiming that the C7 will deliver up to 26 mpg highway.

The new technology on the new LT1 V8 includes direct injection with “on demand” adjustable pressure, variable valve timing, a twisted-head design, and cylinder-deactivation. The new LT1 will also be claimed 40-pounds lighter and four inches shorter than BMW's 4.4L twin-turbo V8.

The new LT1 V8 will be built at GM's Tonawanda plant, the same place where the first Chevy Small Block V8 was built in 1955.

Helps deliver estimated 0-60 performance in less than four seconds and best-ever fuel economy in the Corvette

DETROIT – When the all-new 2014 Chevrolet Corvette arrives late next year, it will be powered by a technologically advanced, racing-proven 6.2L V-8 delivering an estimated 450 horsepower and helping produce 0-60 times in less than four seconds.

The new Corvette LT1 engine, the first of the Gen 5 family of Small Block engines, combines several advanced technologies, including direct injection, Active Fuel Management and continuously variable valve timing to support an advanced combustion system.

“Our objective for the development of the all-new LT1 was to raise the bar for performance car engines,” said Mary Barra, senior vice president, global product development. “We feel that we have achieved that by delivering a true technological masterpiece that seamlessly integrates a suite of advanced technologies that can only be found on a handful of engines in the world.

“What makes this engine truly special is the advanced combustion system that extracts the full potential of these technologies. The art and science behind that combustion system make the Corvette LT1 one of the most advanced V-8 engines in the world,” said Barra.

Output, performance, and fuel economy numbers will not be finalized until early next year, but the new LT1 engine is expected to deliver:

The quickest standard Corvette ever, with estimated 0-60 performance of less than four seconds

The most fuel-efficient Corvette ever, exceeding the 2013 EPA-estimated 26 miles per gallon on the highway.

“The Holy Grail for developing a performance car is delivering greater performance and more power with greater fuel economy and that’s what we’ve achieved,” said Tadge Juechter, Corvette chief engineer. “By leveraging technology, we are able to get more out of every drop of gasoline and because of that we expect the new Corvette will be the most fuel-efficient 450 horsepower car on the market.”

Advanced combustion system optimized with 6 million hours of analysis

“The Corvette LT1 represents the most significant redesign in the Small Block’s nearly 60-year history – building on its legacy to make one of the world’s best engines even better,” said Sam Winegarden, vice president, Global Powertrain Engineering. “More than just great horsepower, the LT1 has been optimized to produce a broader power band. Below 4,000 rpm, the torque of the Corvette LT1 is comparable to that of the legendary, 7.0L LS7 out of the current Corvette Z06. The LT1 is a sweetheart of a power plant and drivers will feel its tremendous torque and power at every notch on the tachometer.”

Increased power and efficiency were made possible by an unprecedented level of analysis, including computational fluid dynamics, to optimize the combustion system, the direct injection fuel system, active fuel management and variable valve timing systems that support it. More than 10 million hours of computational analysis were conducted on the engine program, including 6 million hours (CPU time) dedicated to the advanced combustion system.

Direct injection is all-new to the engine architecture and is a primary contributor to its greater combustion efficiency by ensuring a more complete burn of the fuel in the air-fuel mixture. This is achieved by precisely controlling the mixture motion and fuel injection spray pattern. Direct injection also keeps the combustion chamber cooler, which allows for a higher compression ratio. Emissions are also reduced, particularly cold-start hydrocarbon emissions, which are cut by about 25 percent.

Continuously variable valve timing, which GM pioneered for overhead-valve engines, is refined to support the LT1 AFM and direct injection systems to further optimize performance, efficiency and emissions.

These technologies support the all-new, advanced combustion system, which incorporates a new cylinder-head design and a new, sculpted piston design that is an integral contributor to the high-compression, mixture motion parameters enabled by direct injection.

The LT1 head features smaller combustion chambers designed to complement the volume of the unique topography of the pistons’ heads. The smaller chamber size and sculpted pistons produce an 11.5:1 compression ratio, while the head features large, straight and rectangular intake ports with a slight twist to enhance mixture motion. This is complemented by a reversal of the intake and exhaust valve positions, as compared to the previous engine design. Also, the spark plug angle and depth have been revised to protrude farther into the chamber, placing the electrode closer to the center of the combustion to support optimal combustion.

The pistons feature unique sculpted topography that was optimized via extensive analysis to precisely direct the fuel spray for a more complete combustion. The contours of the piston heads are machined to ensure dimensional accuracy – essential for precise control of mixture motion and the compression ratio.

Race-proven legacy, state-of-the-art performance

The first Small Block V-8 debuted in the Corvette in 1955. It displaced 4.3L (265 cubic inches) and was rated at 195 horsepower, drawing air and fuel through a four-barrel carburetor. Five years later, V-8 power helped Corvette secure its first victory at the 24 Hours of Le Mans.

In 2012, the Small Block-powered Corvette Racing C6.R beat Ferrari, BMW and Porsche to sweep the drivers’, team, and manufacturer championships in production-based American Le Mans Series GT class. These championships make Corvette Racing the most successful team in ALMS history, with a total of 77 class wins, eight drivers’ championships, and nine manufacturer and team championships since 2001.

“The engine requirements for a production car and a race car are remarkably similar,” said Jordan Lee, Small Block chief engineer and program manager. “In both cases, you want an engine that is powerful and efficient, compact and lightweight, and durable. That combination is what made the original Small Block so successful. Today, the introduction of state-of-the-art technologies and engineering makes one of the best performance car engines in the world even better.”

As an example, the new LT1 engine is 40 pounds lighter than a competitor’s twin-turbo 4.4L, DOHC V-8 with similar output. That weight savings not only improves the Corvette’s power-to-weight ratio, but also contributes to a near-perfect 50/50 weight balance for enhanced steering response and handling.

The new LT1 is also four inches shorter in overall height than the competitive DOHC V-8. That also improves handling by lowering the center of gravity while enabling a low hood line – contributing to the Corvette’s iconic profile, as well as ensuring exceptional driver visibility.

The new LT1 is the third engine in the Corvette’s history to be so-named, with previous versions introduced in 1970 (Gen 1) and 1992 (Gen 2). All iterations of the LT1 – and all Small Block engines – have shared a compact design philosophy that fosters greater packaging flexibility in sleek vehicles such as the Corvette.

“The power and efficiency of the Small Block V-8 are hallmarks of Corvette performance,” said Lee. “But, the compact size and great power-to-weight are just as important for the overall driving experience. The all-new LT1 will play a huge role in making the all-new Corvette a world-class sports car, in terms of technology, performance, and refinement.”

Engine features and highlights

All-aluminum block and oil pan: The Gen 5 block was developed with math-based tools and data acquired in GM’s racing programs, providing a light, rigid foundation for an impressively smooth engine. Its deep-skirt design helps maximize strength and minimize vibration. As with the Gen 3 and Gen 4 Small Blocks, the bulkheads accommodate six-bolt, cross-bolted main-bearing caps that limit crank flex and stiffen the engine’s structure. A structural aluminum oil pan further stiffens the powertrain.

The block features nodular iron main bearing caps, which represent a significant upgrade over more conventional powdered metal bearing caps. They are stronger and can better absorb vibrations and other harmonics to help produce smoother, quieter performance.

Compared to the Gen 4 engine, the Gen 5’s cylinder block casting is all-new, but based on the same basic architecture. It was refined and modified to accommodate the mounting of the engine-driven direct injection high-pressure fuel pump. It also incorporates new engine mount attachments, new knock sensor locations, improved sealing and oil-spray piston cooling.

Advanced oiling system, with available dry-sump system: The LT1 oiling system – including oil-spray piston cooling – was also optimized for improved performance. It is driven by a new, variable-displacement oil pump that enables more efficient oil delivery, per the engine’s operating conditions. Its dual-pressure control enables operation at a very efficient oil pressure at lower rpm coordinated with AFM and delivers higher pressure at higher engine speeds to provide a more robust lube system for aggressive engine operation.

Standard oil-spray piston cooling sprays the underside of each piston and the surrounding cylinder wall with an extra layer of cooling oil, via small jets located at the bottom of the cylinders. For optimal efficiency, the oil jets are used only when they are needed the most: at start-up, giving the cylinders extra lubrication that reduces noise, and at higher engine speeds, when the engine load demands, for extra cooling and greater durability.

An available dry-sump oiling system promotes exceptional lubrication system performance during aggressive driving maneuvers and high cornering loads. It includes two stages: a pressure stage and a scavenge stage. The pressure stage includes the new, dual-pressure-control and variable-displacement vane pump.

New, tri-lobe camshaft: Compared to the Gen 4 Small Block, the camshaft remains in the same position relative to the crankshaft and is used with a new rear cam bearing, but it features an all-new “tri-lobe” designed lobe which exclusively drives the engine-mounted direct injection high-pressure fuel pump, which powers the direct-injection combustion system. The cam’s specifications include 14mm/13.3mm (0.551/0.524-inch) intake/exhaust lift, 200/207-crank angle degrees intake/exhaust duration at 0.050-inch tappet lift and a 116.5-degree cam angle lobe separation.

New, cam-driven fuel pump: The direct injection system features a very-high-pressure fuel pump, which delivers up to 15Mpa (150 bar). The high-pressure, engine-driven fuel pump is fed by a conventional fuel-tank-mounted pump. The direct injection pump is mounted in the “valley” between cylinder heads – beneath the intake manifold – and is driven by the camshaft at the rear of the engine. This location ensures any noise generated by the pump is muffled by the intake manifold and other insulation in the valley.

PCV-integrated rocker covers: One of the most distinctive features of the new engine is its domed rocker covers, which house the, patent-pending, integrated positive crankcase ventilation (PCV) system that enhances oil economy and oil life, while reducing oil consumption and contributing to low emissions. The rocker covers also hold the direct-mount ignition coils for the coil-near-plug ignition system. Between the individual coil packs, the domed sections of the covers contain baffles that separate oil and air from the crankcase gases – about three times the oil/air separation capability of previous engines.

Acoustic foam is sandwiched between the outside top of the intake manifold and an additional acoustic shell to reduce radiated engine noise, as well as fuel pump noise.

The manifold is paired with an electronically controlled throttle, featuring an 87mm bore diameter and a “contactless” throttle position sensor design that is more durable and enables greater control.

Four-into-one exhaust manifolds: The LT-1 uses a cast version of the “four-into-one” short-header exhaust manifold design used on the Gen 4 LS7 engine. The cast header passages enable consistent exhaust flow into the “wide mouth” collector at the converter.

Cooling system, humidity sensor and more: Additional features and technologies of the Gen 5 Small Block include:

A revised cooling system with an offset water pump and thermostat for more efficient performance

General Motors’ investment in the Gen 5 Small Block will create or retain more than 1,600 jobs in five North American plants, including Tonawanda, New York, which recently received upgrades to support its production.

William Maley is a staff writer for Cheers & Gears. He can be reached at william.maley@cheersandgears.com or you can follow him on twitter at @realmudmonster.

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I am excited by this engine and will be waiting to see what the Performance division does to take it to the next level. I suspect this engine has a ton more potential than they are initially giving in the base corvette.

So BMW does 400HP/450ft lbs in a twin turbo V8 that is only 4.4L and this 6.2L is smaller and yet more powerful.

* This may indicate a relatively low red line (perhaps 6000~6100 rpm) perhaps imposed by the the cylinder deactivation system.

** 438 lb-ft was based on the limit of the 6L80 transmission.

Regardless, this engine is in the ballpark of expectations and will serve the C7 very well. It will also serve Cadillac very well should they elect to adopt it for the ATS-V. It is, afterall, a lighter, smaller, more powerful and more torque engine than the Ford DOHC 5.0. It is also lighter, simpler and less expensive than Bi-turbo V6es of a similar output.

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Nice engine and I wish they would put the Small Block name to rest as it deserves it's own heritage. The number of parts that carry over from the LS engine can fit in a small Zip Loc bag.

Well the injectors will be buried for those who don't like the noise. I just hope they are easy to get to to replace them or that they are at the least durable.

Too many idiots on Autoblog are complaining only 450 HP from 6.2? They seem to not read all the words that it will be no less than 450 HP. I still expect 460-470 HP by the release time. They said the base Vette would run with the present Grandsport.

I still do not expect this in the ATS V but it will be in the new CTSV.

The Z06 and ZR1 replacments should be interesting.

I note they played with the valves like many of the aftermarket head companys have to get better flow. Trick Flow started it and many others hav followed with canting the valves. We found them to work years ago and GM has their own version now.

Owners who add fuel pressure monitors will be shocked when they see over 2000 PSI on the High pressure pump side.

What I found interesting was the choice of 6.2. They said it was because when the engine would go into V4 mode that there was too little power in the smaller engine. They said by increasing the size it gave the V4 mode enough power to remain in V4 mode for more MPG. The smaller engine would have been in V8 mode more and payed the MPG penalty. It had noting to do with efficency but with available power with 4 cylinders cut out.

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I still do not expect this in the ATS V but it will be in the new CTSV.

The Z06 and ZR1 replacments should be interesting.

Regardless of whether the ATS-V gets this engine, the CTS-V won't. The CTS-V is already at 556hp with the current LSA engine. It's replacement will need to be either a turbocharged or supercharged version of the LT1 to be at or above the current performance level.

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Nice numbers. Though ultimately I think I'm more of a smaller displacement, higher rev V8 sort of guy. I hope they also offer a 5.3L version with the same power, less torque, and a redline that exceeds 7,000 RPM.

I had a Mustang GT 5.0 loaner two weeks ago, and man was that motor addictive. Had the grumble of an American V8 at low revs and the zing of an M3 or RS4 near redline.

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Nice numbers. Though ultimately I think I'm more of a smaller displacement, higher rev V8 sort of guy. I hope they also offer a 5.3L version with the same power, less torque, and a redline that exceeds 7,000 RPM.

I had a Mustang GT 5.0 loaner two weeks ago, and man was that motor addictive. Had the grumble of an American V8 at low revs and the zing of an M3 or RS4 near redline.

Not sure if we will see a smaller V8 based on the Cylinder delete option. This is where GM claims a lot of MPG is gained and the smaller displacment just does not handle the power well with 4 cylinders.. They claim it would remain in V8 mode too much. Now if there were not a cylinder delet option being used we would have seen the smaller engine.

The think with this engine is it will have torque from down low and hold it most of the way up like my Turbo Eco does. This will give this engine a feel unlike the LS3.

The coming Turbo V6 will be the engine with more and faster revs but it too will also have low end torque that will remain all the way up. It will also have a noticable lack lag too.

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I still do not expect this in the ATS V but it will be in the new CTSV.

The Z06 and ZR1 replacments should be interesting.

Regardless of whether the ATS-V gets this engine, the CTS-V won't. The CTS-V is already at 556hp with the current LSA engine. It's replacement will need to be either a turbocharged or supercharged version of the LT1 to be at or above the current performance level.

The CTSV will get an engine based on this and we all know it will have a turbo or more than likely a supercharger. MY statment is that this engine is the base for all variation coming at GM. They may slap a supercharger on it and a LT5 name but it will be based on this engine with some changes just as the LS engines were. There will be a family of LT engines just as the LS engines.

If anything I have heard numbers in the 600+ range may be in the offing for the CTS and the number 750 HP ZRI have been rumored. Just have to wait and see, but both are very easily done.

Anyone else have the feeling that a 5.5L LTx engine is still in the cards?

There was talk of a V6 version of this engine but nothing to prove that yet.

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What is it with GM and these "required" fluids? First it was Dexcool antifreeze, and that was somewhat of a disaster with all the clogged-up radiators and engine cooling passages. Now they're requiring the use of this Dexos semi-synthetic motor oil. I hope this doesn't turn into another bad idea. I think I read where they'll void your warranty unless Dexos is used and documented, if someone can confirm or deny for me.

It's one thing, for example, to "recommend" Mobil 1 in the Corvette, but this Dexos situation, requiring its use on everything from Spark to XTS, seems like extortion to me. Besides... SO many things happen when cars are in the hands of customers. Jiffy Lube... Wal-Mart service centers... any number of mom-and-pop garages will be changing the oil on these cars in years hence. I predict another debacle and future ill will toward GM on behalf of customers over this.

Seems like any 5W-30 should suffice. GM is citing fuel economy concerns as a reason for instituting this policy, but it sounds to me like they want everyone to go to the dealership for maintenance... or else.

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Dexos is just an oil rating. There are many many different Dexos rated oils. They are all basically the 5w-30 version of a brand's full synthetic product. It's actually better than recommending Mobile 1 because it is now not brand specific. Ask yourself this, why would GM want to be stamping Mobile1's brand on the engine cover of all of their products?

But there is very little debate over whether synthetic oil is more healthy for an engine or not. It is... and it is within GM's rights to require its use for the car to be under warranty.

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See how that works? Thanks for posting that link. So, a whole host of brands are approved for the Dexos1 rating, both full synthetic and synthetic blends. That will make a lot of GM buyers feel a bit better about this new requirement, even though it does require customers to spend more money on oil... and they'll just go back every 3,000 miles like the sticker on the windshield says, they won't pay attention to the DIC or the owner's manual.

* This may indicate a relatively low red line (perhaps 6000~6100 rpm) perhaps imposed by the the cylinder deactivation system.

** 438 lb-ft was based on the limit of the 6L80 transmission.

Regardless, this engine is in the ballpark of expectations and will serve the C7 very well. It will also serve Cadillac very well should they elect to adopt it for the ATS-V. It is, afterall, a lighter, smaller, more powerful and more torque engine than the Ford DOHC 5.0. It is also lighter, simpler and less expensive than Bi-turbo V6es of a similar output.

This LT1 engine weights 465 lbs. Coyote v8 weights 430 lbs. it is also heavier than M156 or M159 engine from Mercedes.

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See how that works? Thanks for posting that link. So, a whole host of brands are approved for the Dexos1 rating, both full synthetic and synthetic blends. That will make a lot of GM buyers feel a bit better about this new requirement, even though it does require customers to spend more money on oil... and they'll just go back every 3,000 miles like the sticker on the windshield says, they won't pay attention to the DIC or the owner's manual.

Unless they are really stupid customers to ignore their engine info center, most people should come to realize that we are at the end of days with the BS 3000 miles you change the oil. That was true of older cars of the 90's and older than that, but not with todays cars and the use of synthetic or blends, you should be able to go 7500 to 10K miles now on an oil change.

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Yes sir, I use the DIC to tend to my oil changes. But these oil change shops are still pushing 3k oil changes, and writing it on the oil change sticker.

I use Albert as my "consumer focus group - subgroup: people dumb about cars".... in the nicest way possible of course. Anyone who drives a Honda or Toyota has been conditioned into thinking that when the "Service Required Soon" light starts flashing, then it is time to get an oil change. It could be 3,000 miles or 15,000 miles... they ignore the sticker as long as that light isn't on.

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Yes sir, I use the DIC to tend to my oil changes. But these oil change shops are still pushing 3k oil changes, and writing it on the oil change sticker.

I use Albert as my "consumer focus group - subgroup: people dumb about cars".... in the nicest way possible of course. Anyone who drives a Honda or Toyota has been conditioned into thinking that when the "Service Required Soon" light starts flashing, then it is time to get an oil change. It could be 3,000 miles or 15,000 miles... they ignore the sticker as long as that light isn't on.

Very true and now with GM, Ford and pretty much everyone telling you to just follow the computer for when to get oil changes, etc. If the computer does not tell them, most will ignore the 3K that a grease monkey puts on the window.

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While the MFG's are trying to make use of the better oils and the better quality engines to make you new car more economical by not having to change oil as often. The problem is it is taking money out of the pockets of oil change shops and dealer service shop.

The average car owner seldom reads the owners manual because he already knows how to drive the car and set the radio. He has had it beat through his head to change at 3,000 miles but has no idea how good oils are today and how the OLM really works and what all goes into it. Hell I just read the other day a NOX owner though he had too much fuel in his oil so he changed it and now thinks it is running smoother. The truth was he may have just had some bad gas as an oil change would not have fixed the condition he discribed.

GM should so more to explain the OLM as well as the Dexos deal. I see even many gear heads that do not understand what they are doing here. The fact is many cars in the future will need special oils and the MFG's want to be the ones who decide what they need not the oil companies. Also it add some extra income to a limited degree.

As for Dexcool there is nothing wrong with it other than the lack of knowledge. Too many people condem it because they may have had an issue but the fact is most people have never had an issue. The fact is you have to keep a good strong mix of this fluid in the system as if it is weak or has air in the system it will sludge up. The tolerance on this product is tighter than the average green prestone. If used properly there is nary an issue with this anti freeze. But then again it is the lack of info from GM on how to deal with it.

While I blame GM for not passing out the info in a better way the owners also need to accept that todays cars have changed a lot more than they think. Things we used to do the old way do not apply any longer. If you do not read or take training to keep up best to let the pros do it anymore. Case in point the new DI system is not your old fuel injection. There are things to learn and know like how high the pressure is and that many of the lines are one time use and need to be replaced if removes. But some guy at home will try to do it the old way and muck it up.

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I also expect the heads are larger and would not be suprised if the strengthened the block even more. GM has been adding more structure to their engines. In many cases it is worth a little weight.. We will have to watch to see what the parts weigh in at to tell. But the engine is still not bad.